Series
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๐ Comprehensive Syllabus & Examination Guide
Series
Official curriculum roadmap, subject/topic distribution, negative marking rules, pacing guidelines, and solved sample questions.
๐ฏ Mapped Subjects & Topic Question Distribution
Total Question Pool
100%
156 MCQs
Combined Active Syllabus
Series
156 MCQs
Topic Pool
๐ Question Pool Structure
156 MCQs across fundamental, intermediate, and advanced concept tiers.
โก Recommended Pacing
45 to 60 seconds per MCQ. Flag complex problems and preserve 10 minutes for final revision.
โ๏ธ Scoring & Negative Marking
+1 mark per correct answer. In competitive tests with negative marking, -0.25 applies for incorrect guesses.
๐ก Strategic Preparation & Exam Hall Guidelines
To maximize your score on Series, candidates are advised to follow a structured three-pass approach. In the First Pass, solve all direct recall and formula-based questions within 30 seconds each to secure foundational marks. In the Second Pass, tackle multi-step analytical and quantitative reasoning problems. In the Third Pass, review marked questions and verify calculations.
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Solved Blueprint Examples
Showing 10 solved representative questions
๐ Pre-Rendered Solved Sample Questions & Detailed Solutions
Review the solved problems below to understand question phrasing, answer choices, and step-by-step solution logic prior to starting the full interactive practice drill:
Sample Question 1
Series
Hard • Intelligence Tests
Find the valve of X in the following: 9 1 25 64 / 16 4 X 81 / 25 9 49 100
A
121
B
36
C
25
D
49
โ Correct Answer: B - 36
๐ Step-by-Step Solution & Conceptual Rationale:
Every number in the grid is a perfect square. If you look at the square roots of the numbers column by column, they increase by exactly 1 as you go down each row:
Column 1: \(\sqrt{9}=3\) \(\rightarrow \) \(\sqrt{16}=4\) \(\rightarrow \) \(\sqrt{25}=5\)
Column 2: \(\sqrt{1}=1\) \(\rightarrow \) \(\sqrt{4}=2\) \(\rightarrow \) \(\sqrt{9}=3\)
Column 4: \(\sqrt{64}=8\) \(\rightarrow \) \(\sqrt{81}=9\) \(\rightarrow \) \(\sqrt{100}=10\)
Following this exact pattern for Column 3:
Row 1: \(\sqrt{25} = 5\)
Row 2: Must be \(6\) (since \(5 + 1 = 6\))
Row 3: \(\sqrt{49} = 7\)
Since the square root must be 6, the value of X is \(6^2 = \mathbf{36}\).
Column 1: \(\sqrt{9}=3\) \(\rightarrow \) \(\sqrt{16}=4\) \(\rightarrow \) \(\sqrt{25}=5\)
Column 2: \(\sqrt{1}=1\) \(\rightarrow \) \(\sqrt{4}=2\) \(\rightarrow \) \(\sqrt{9}=3\)
Column 4: \(\sqrt{64}=8\) \(\rightarrow \) \(\sqrt{81}=9\) \(\rightarrow \) \(\sqrt{100}=10\)
Following this exact pattern for Column 3:
Row 1: \(\sqrt{25} = 5\)
Row 2: Must be \(6\) (since \(5 + 1 = 6\))
Row 3: \(\sqrt{49} = 7\)
Since the square root must be 6, the value of X is \(6^2 = \mathbf{36}\).
Sample Question 2
Series
Hard • Intelligence Tests
4 9 20 ... 5 11 24 8 17 ( )
A
35
B
45
C
36
D
48
โ Correct Answer: C - 36
๐ Step-by-Step Solution & Conceptual Rationale:
Identified as the next logical step in the grid's numerical progression. [Key: 9(c)].
Sample Question 3
Series
Hard • Intelligence Tests
6 9 21 ... 10 5 15 10 3 ( )
A
18
B
21
C
11
D
25
โ Correct Answer: C - 11
๐ Step-by-Step Solution & Conceptual Rationale:
Progression logic in the provided digit grid identifies 11 as the missing element. [Key: 13(c)].
Sample Question 4
Series
Medium • Quantitative Aptitude Test
Find the odd man out: 3 6 9 12 15 17
A
15
B
17
C
3
D
9
E
6
โ Correct Answer: B - 17
๐ Step-by-Step Solution & Conceptual Rationale:
17 is the only number in the sequence that is not a multiple of 3.
Sample Question 5
Series
Medium • Quantitative Aptitude Test
Series: 16, 23, 20, 27, 24, 31, โโ?
A
24
B
27
C
26
D
28
โ Correct Answer: D - 28
๐ Step-by-Step Solution & Conceptual Rationale:
The Pattern
This sequence follows an alternating mathematical pattern of adding 7, then subtracting 3:
\(16 + 7 = 23\)
\(23 - 3 = 20\)
\(20 + 7 = 27\)
\(27 - 3 = 24\)
\(24 + 7 = 31\)
Solving for the Next Number
Following the established pattern, the next operation is to subtract 3:
\(31-3=\mathbf{28}\)
This sequence follows an alternating mathematical pattern of adding 7, then subtracting 3:
\(16 + 7 = 23\)
\(23 - 3 = 20\)
\(20 + 7 = 27\)
\(27 - 3 = 24\)
\(24 + 7 = 31\)
Solving for the Next Number
Following the established pattern, the next operation is to subtract 3:
\(31-3=\mathbf{28}\)
Sample Question 6
Series
Medium • Quantitative Aptitude Test
Series: 3, 7, 3, 9, 3, 11, 3, โโ?
A
11
B
12
C
13
D
14
E
15
โ Correct Answer: C - 13
๐ Step-by-Step Solution & Conceptual Rationale:
Alternating series: Constant 3 interleaved with +2 progression (7,9,11,13).
Sample Question 7
Series
Medium • Quantitative Aptitude Test
Series: 4, 7, 9, 11, 14, 15, 19, โโ?
A
20
B
17
C
18
D
19
โ Correct Answer: D - 19
๐ Step-by-Step Solution & Conceptual Rationale:
This sequence is made by interleaving two different arithmetic progressions (alternating terms):
Odd positions (1st, 3rd, 5th, 7th numbers) increase by +5:
\(4\xrightarrow{+5}9\xrightarrow{+5}14\xrightarrow{+5}19\)
Even positions (2nd, 4th, 6th, 8th numbers) increase by +4:
\(7\xrightarrow{+4}11\xrightarrow{+4}15\xrightarrow{+4}\mathbf{19}\)
Since the next number fills the 8th position (an even slot), we follow the second pattern:
\(15 + 4 = 19\).
Odd positions (1st, 3rd, 5th, 7th numbers) increase by +5:
\(4\xrightarrow{+5}9\xrightarrow{+5}14\xrightarrow{+5}19\)
Even positions (2nd, 4th, 6th, 8th numbers) increase by +4:
\(7\xrightarrow{+4}11\xrightarrow{+4}15\xrightarrow{+4}\mathbf{19}\)
Since the next number fills the 8th position (an even slot), we follow the second pattern:
\(15 + 4 = 19\).
Sample Question 8
Series
Hard • Quantitative Aptitude Test
Continue the series
(i) 10, 14, 9, 15, 8, 16, __, __
(ii) 15, 6, 13, 6, 11, 6, __, __
(i) 10, 14, 9, 15, 8, 16, __, __
(ii) 15, 6, 13, 6, 11, 6, __, __
A
7, 17 and 8, 6
B
7, 15 and 9, 6
C
9, 17 and 9, 4
D
7, 17 and 9, 6
E
6, 18 and 10, 6
โ Correct Answer: D - 7, 17 and 9, 6
๐ Step-by-Step Solution & Conceptual Rationale:
Series 1:
The sequence alternates between subtracting 1 from the odd positions (\(10 \rightarrow 9 \rightarrow 8 \rightarrow \mathbf{7}\)) and adding 1 to the even positions (\(14 \rightarrow 15 \rightarrow 16 \rightarrow \mathbf{17}\)).
Series 2:
The odd-positioned numbers decrease consistently by 2 (\(15 \rightarrow 13 \rightarrow 11 \rightarrow \mathbf{9}\)), while the even-positioned numbers remain static as the value 6.
The sequence alternates between subtracting 1 from the odd positions (\(10 \rightarrow 9 \rightarrow 8 \rightarrow \mathbf{7}\)) and adding 1 to the even positions (\(14 \rightarrow 15 \rightarrow 16 \rightarrow \mathbf{17}\)).
Series 2:
The odd-positioned numbers decrease consistently by 2 (\(15 \rightarrow 13 \rightarrow 11 \rightarrow \mathbf{9}\)), while the even-positioned numbers remain static as the value 6.
Sample Question 9
Series
Hard • Quantitative Aptitude Test
Series:
15, 6, 13, 6, 11, 6, __, __
15, 6, 13, 6, 11, 6, __, __
A
9, 6
B
9, 4
C
8, 6
D
10, 6
โ Correct Answer: A - 9, 6
๐ Step-by-Step Solution & Conceptual Rationale:
The odd-positioned numbers decrease consistently by 2 (\(15 \rightarrow 13 \rightarrow 11 \rightarrow \mathbf{9}\)), while the even-positioned numbers remain static as the value 6.
Sample Question 10
Series
Hard • Quantitative Aptitude Test
Insert the missing numbers:
7, 9, 18, 24, 51, __, __, 150, 204
7, 9, 18, 24, 51, __, __, 150, 204
A
65, 142
B
69, 150
C
72, 160
D
68, 148
โ Correct Answer: B - 69, 150
๐ Step-by-Step Solution & Conceptual Rationale:
This sequence is determined by looking at the differences between consecutive terms, which follow two alternating geometric progressions that both multiply by 3 at each step:
First Difference Series (Odd transitions):
\(9 - 7 = \mathbf{2}\)
\(24 - 18 = \mathbf{6}\) \((2 \times 3)\)
\(\text{Next difference} = 6 \times 3 = \mathbf{18}\)
\(\text{Following difference} = 18 \times 3 = \mathbf{54}\)
Second Difference Series (Even transitions):
\(18 - 9 = \mathbf{9}\)\(51 - 24 = \mathbf{27}\) \((9 \times 3)\)
\(\text{Next difference} = 27 \times 3 = \mathbf{81}\)
Find the 6th number:
Add the next difference (\(18\)) to the 5th number (\(51\)):
\(51+18=\mathbf{69}\)
Find the 7th number:
Add the next difference (\(81\)) to the newly found 6th number (\(69\)):
\(69+81=\mathbf{150}\)
Verification of the next term:
Add the next difference (\(54\)) to the 7th number (\(150\)):
\(150+54=\mathbf{204}\)
First Difference Series (Odd transitions):
\(9 - 7 = \mathbf{2}\)
\(24 - 18 = \mathbf{6}\) \((2 \times 3)\)
\(\text{Next difference} = 6 \times 3 = \mathbf{18}\)
\(\text{Following difference} = 18 \times 3 = \mathbf{54}\)
Second Difference Series (Even transitions):
\(18 - 9 = \mathbf{9}\)\(51 - 24 = \mathbf{27}\) \((9 \times 3)\)
\(\text{Next difference} = 27 \times 3 = \mathbf{81}\)
Find the 6th number:
Add the next difference (\(18\)) to the 5th number (\(51\)):
\(51+18=\mathbf{69}\)
Find the 7th number:
Add the next difference (\(81\)) to the newly found 6th number (\(69\)):
\(69+81=\mathbf{150}\)
Verification of the next term:
Add the next difference (\(54\)) to the 7th number (\(150\)):
\(150+54=\mathbf{204}\)
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